get_bkg_chisqr_plot

sherpa.astro.ui.get_bkg_chisqr_plot(id: IdType | None = None, bkg_id: IdType | None = None, recalc=True)

Return the data used by plot_bkg_chisqr.

Parameters:
  • id (int, str, or None, optional) – The data set that provides the data. If not given then the default identifier is used, as returned by get_default_id.

  • bkg_id (int, str, or None, optional) – Identify the background component to use, if there are multiple ones associated with the data set.

  • recalc (bool, optional) – If False then the results from the last call to plot_bkg_chisqr (or get_bkg_chisqr_plot) are returned, otherwise the data is re-generated.

Returns:

chisqr – An object representing the data used to create the plot by plot_bkg_chisqr.

Return type:

a sherpa.astro.plot.BkgChisqrPlot instance

Raises:

See also

get_bkg_delchi_plot

Return the data used by plot_bkg_delchi.

get_bkg_ratio_plot

Return the data used by plot_bkg_ratio.

get_bkg_resid_plot

Return the data used by plot_bkg_resid.

plot_bkg_chisqr

Plot the chi-squared value for each point of the background of a PHA data set.

Examples

>>> bplot = get_bkg_chisqr_plot()
>>> print(bplot)
>>> get_bkg_chisqr_plot('jet', bkg_id=1).plot()
>>> get_bkg_chisqr_plot('jet', bkg_id=2).overplot()